G.f.: Sum_{n>=0} (3^n + 1)^n * x^n / (1 + 3^n*x)^(n+1).

A324307

G.f.: Sum_{n>=0} (3^n + 1)^n * x^n / (1 + 3^n*x)^(n+1).

Terms

    a(0) =1a(1) =3a(2) =77a(3) =19359a(4) =42889529a(5) =846714983643

External references